Which London Underground line is the shortest, running between Waterloo and Bank?

The Waterloo & City line is the shortest London Underground line, running between Waterloo and Bank.

The line is only about 2.37 kilometres long and has two stations: Waterloo and Bank. It opened in 1898 to carry commuters from the mainline terminus at Waterloo into the City of London, the capital's principal financial district. Its short route reflects that very specific commuter purpose.

The line was originally built by the Waterloo & City Railway and was operated by the London and South Western Railway. It later became part of the Underground system and is now managed as a separate line. Because it has no intermediate station, a complete journey takes only a few minutes.

The Waterloo & City is sometimes nicknamed “The Drain,” a traditional name linked to its short underground route. It is not generally a sightseeing line and has historically had restricted operating hours compared with most other Underground lines.